The use of fluorescent lighting is wide spread. Typical fluorescent lighting consists of long slender tubes, typically 4 feet (122 cm) long with a diameter of 1 inch (2.54 cm). This type of lighting typically has a poor color rendering index, making color differentiation by a person difficult. This lighting is not widely used in residential lighting due to the poor aesthetics created by the wavelength distribution of light output from the lamp. Many efforts have been made to utilize LEDs in lamps used to replace fluorescent tubes. Such LED-based replacement lamps provide advantages in that LEDs can be selected that provide color spectrum outputs that give superior color rendering and more aesthetically pleasing light.
One approach used in making LED-based fluorescent tube replacements is to create a large array of LEDs that fit within a cylindrical envelope defined by the dimensions of the fluorescent tube being replaced. Such devices may consist of 100 or more individual LEDs. However, the output is less desirable because the brightness created by each LED evokes a sense of glare from the fixture. Reducing the number of LEDs while increasing the brightness of each LED to maintain a desired light output level only exacerbates the sensation of glare, whereas reducing the size of the LEDs and increasing the number of LEDs increases the overall cost of the device.
A second approach for making an LED-based fluorescent tube replacement, as disclosed in relation to FIG. 38 of Cassarly et al. U.S. Pat. No. 7,374,313, is to use a pair of LED light sources, one at each end of a side-light distribution member. It would be desirable to go beyond the foregoing disclosure and provide a means for holding the side-light distribution member and LED light sources in place.
It would thus be desirable to provide an elongated LED lamp that can replace an elongated fluorescent lamp, while providing a pleasing color distribution of light without high brightness “glare” spots and providing means for holding the side-light distribution arrangement.